In bacterial cells, translation of an RNA transcript begins before transcription is completed. Thus, during normal growth, transcription and translation are coupled. We propose to study the role of protein synthesis in the accumulation, stability, and cellular location of biologically active messenger RNA capable of directing the synthesis of bacteriophage enzymes in vitro. Various inhibitors of protein synthesis, whose mode of action on translation is known, will be used in this study. In this way we plan to elucidate those steps in the translation process which may be necessary for accumulation of functional messenger RNA in vivo. BIBLIOGRAPHIC REFERENCES: Walsh, M. L., Pennica, D., and Cohen, P. S. The distribution of functional bacteriophage T4 mRNA on polysomes. Arch. Biochem. Biophys. 173:732-738, 1976. Walker, A. C., Walsh, M. L., Pennica, D., Cohen, P. S., and Ennis, H. L. Transcription-translation and translation-messenger RNA decay coupling: separate mechanisms for different messengers. Proc. Nat. Acad. Sci. U.S.A. 73:1126-1130, 1976.